if the area of a triangle with the base 2F and height F-2 is equal to F, compute F.

2 answers

solve it just as you would for any other algebra equation. 2x(x-2)=x. Then distribute, to make 2x^2-4x-x=0, then combine like terms: 2x^2-5x=0, factor out a "x"--x(2x-5)=0, so x could equal 0 or x could equal 5/2
The area of a triangle is (1/2)base*height, so
(1/2)2F(F-2)=F
F²-2F=F
F(F-3)=0
F=0 or F=3
Check: (1/2)2*3(3-2)=3 OK.